The photographic news

• Bandzählung: 35.1891
• Erscheinungsdatum: 1891
• Sprache: Englisch
• Signatur: F 135
• Vorlage: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: SLUB Dresden
• Rechtehinweis: Public Domain Mark 1.0
• URN: urn:nbn:de:bsz:14-db-id1780948042-189100009
• PURL: http://digital.slub-dresden.de/id1780948042-18910000
• OAI: oai:de:slub-dresden:db:id-1780948042-18910000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

648 THE PHOTOGRAPHIC NEWS. [September 11, 1891. 9 Messrs. W. B. Funnell, E. Miller, P. Morris, G. J. Wightman, and H. B. Constable, the last-named gentleman being appointed in the place of Mr. C. R. Wells (resigned). The set of hand-camera pictures by Mr. Percy Morris, which gained a silver medal at the Cardiff Photographic Exhibition, were on view in the room, and were much admired. During the evening certificates were presented to Mr. W, Young for enlargements, and Mr. J. Tunks for lantern slides. Richmond Camera Club. September ith.—Mr. Hunter presided. Mr. Richardson showed an actinometer of his own make for timing the printing of platinotype and carbon prints, &c. The subject for discussion was “Testing Lenses.” Mr. Ardaseer explained the mode of testing for faults in mounting and grinding, and the colour of the glass, and for iridescence, bubbles, flare-spots, “ghosts,” spherical aberration, non-coin- cidence of visual and actinic foci, curvilinear distortion, astigmatism, flatness of field, and covering power. Mr. CENBRAXO added some remarks on polish and striation, and the importance of accurately measuring the focal length of the lens and the apertures of the stops, and showed some plates which he had exposed to test covering power. Outings took place on the 32nd ult. to Cobham, and on the Sth inst. to Pinner, with fine weather on each occasion. Leeds PHOTOGRAPHIC Society. The first meeting after the summer vacation was held on the 1st. inst., Dr. Jacob in the chair. The evening was devoted to an exhibition of negatives, prints, &c., taken during the holidays. Amongst the exhibits the following may be mentioned: Mr. Robert Bownas, aristotype prints ; Mr. T. Butterworth, a fine collection of 12 by 10 prints in silver and Obernetter paper ; Mr. A. R. Dayson, hand-camera views ; Mr. Herbert Denison, 7J by 5 and hand camera prints on Obernetter and platinotype ; Mr. E. Kinsley, half and whole-plate Obernetter prints ; Mr. A. A. Pearson, a large collection of hand-camera views of Whitby and neigh bourhood ; Mr. R. W. Savage, Obernetter and matt surface prints ; Mr. H. S. Walker, negatives of Derwentwater, &e. ; Mr. S. A. Warburton, pictures mounted in optical contact with the glass. A very agreeable evening was spent in discussing the various exhibits and processes involved. The next meeting will be held on the 21st instant in the .Society’s room, Mechanics’ Institution, when Mr. G. H. Rodwell will give a demonstration of “ Lantern Slide Making.” Errata.—In Mr. P. H. Emerson’s letter on “ Perspective Drawing and Vision,” in our issue of 28th ult., there are a few printer’s errors, which escaped correction by mislay of copy :— 1st line, omit “the”; line 12, for “ will,” read “theory”; line 16, for “in," read “id”; line 18, for “say again,” read “ only agree ”; omit comma. The Hackney Photographic Society’s Exhibition is to be held at Morley Hall, Triangle, Hackney, on the 21st and 22nd of October. There is to be an open competition in lantern slides, for the best six of which a silver medal will be awarded ; and there will be also an open class, for any picture by any process, except opals or transparencies, in which the award will be made of a gold, silver, and bronze medal for the three best pictures. The judges will be Messrs. J. Traill Taylor and A. Pringle. Sir Charles Russell, Q.C., M.P., has consented to perform the opening ceremony. In addition to the usual display of pictures for competition, the committee have arranged for popular entertainments, which will include concert and organ recitals, working trade exhibits, optical lantern displays, exhi bition of photographic apparatus, &c. .The prize distribution will be held on Thursday evening, when four gold, eight silver, and three bronze medals, besides other valuable prizes, will be awarded. Admission each day, one shilling. Further par ticulars and conditions of exhibition can be obtained of W. Fenton Jones, Hon. Sec., 6, Victoria Street, King Edward Road, N.E, Anslers to Correspondents. All Advertisements and communications relating to money matters, or to the sale of the paper, should be addressed to the Publishers of the Paorog2apare News, Messrs. Piper & Carter, 5, Furnival Street, London. All Communications, except advertisements, intended for publication, should be addressed to the Editor of the Paorognaparo News, 6, Furnival Street, London, E.C. J. C. (Northwich).—Gelatine Plates and, Collodion. 1. Thin, soft negatives with proper exposure should be sufficiently developed in five minutes, but for vigorous subjects requiring greater contrasts, ten minutes might be better. Alum bath, if used at all, need be but a short operation, say one to two minutes. Remember to wash before fixing, and leave the plate in the hypo until all the yellow bromide has been dissolved out. 2. Ten grains of pyroxyline, and five grains each of cadmium bromide and iodide, might be the right proportions for two ounces of collodion, but here again there is room for the exercise of judgment, the composition being varied according to the requirements of the case, and no two samples of gun-cotton are alike, those prepared at low temperatures giving a thicker collodion. H. D. (Surbiton).—Pall Mall Exhibition. See notice given last week. Wednesday next will be the receiving day for frames, lantern slides, and apparatus delivered by hand at the Gallery. PHOTARGUS.—Black-and-White Work. 1. Will not a dilute bath of cyanide help you to clear the shadows previous to mercury intensification ? 2. Schlippe’s salt, being an alkaline preparation, might not answer so well on a gelatine plate as with collodion, but you should try it. 3. Tincture of iodine will convert a gelatine negative into a yellow picture, but without really adding to its intensity, as we have proved by direct experiments. Another mode of intensification is that mentioned by Mr. W. T. Wilkinson at page 12 of his book on “ Photo-Engraving,” viz : — Red prussiate ,.. ... ... ... 6 parts Nitrate of lead ... ... ... ... 4 „ Water ... ... ... ... ... 80 ,, When bleached and washed, the plate is treated with dilute nitric acid, 1 to 80 ; again well washed, and flooded with sulphide of ammonium diluted with five times its bulk of water. Lastly, treat with the same dilute nitric acid, wash, and dry. Old Stock.—Cracked Glaze. You cannot do better than warm the old dishes and rub melted paraffin or white wax into the cracks ; even then such vessels should only be used for inferior purposes. Old glasses are worth looking over to select out the best squares for photographic use or framing, all the rest being drafted off to the horticulturist. Torres.—Luminous Paint. This can still be obtained of Mr. Horne, 6, Dowgate Hill, E.C. It is generally used only as a last coating to save expense. Len. — British Association. The official report of the Cardiff meeting will not be issued until next March or April ; mean while the scientific papers are appearing in the Chemical News, Nature, Engineer, Electrician, and other class journals, taking special notice of communications interesting to their readers. The South Wales Daily News (Cardiff, St. Mary’s Street), from 19th to 26th ult., gave good summaries of the general proceedings in the various sections, and to these, or the Times reports, you might turn in the first instance for preliminary information. E. M. (Crewe).—Eoside of Silver. The facts are not quite as you have stated, for the eosines and erythrosines always con tain chlorine, bromine, or iodine, and these halogens are necessary constituents of the organo-silver compound formed on precipitating an aqueous solution of the colouring matter with nitrate of silver. Fluoresceine can be worked in with the eosines, but not magenta, unless alcohol be employed. Have you tried naphthaline red, “ Rose de Magdala ”? Ed. L. Wilson.—Your letter has been sent on to South Kensington.